That will be an uphill battle for Wehby in the blue state — but her primary success is a triumph for party operatives who hope the recruit can appeal to moderate and female voters and, as a doctor, credibly criticize the Affordable Care Act and its troublesome rollout in Oregon.

“Dr. Wehby is an exciting candidate, a mom, and a pediatric neurosurgeon who has dedicated her life to healing children and has firsthand knowledge when it comes to Oregonians’ health care needs,” National Republican Senatorial Committee Chairman Jerry Moran in a statement. “Democrats are now on defense in Oregon.”

A political newcomer, Wehby enjoyed frontrunner status thanks to much stronger fundraising than Conger, endorsements from high-profile GOP leaders like Mitt Romney and the support of several independent-expenditure groups.

Her campaign and a supportive super PAC also sustained scrutiny because the ex-boyfriend, lumber executive Andrew Miller, cut a five-figure check to the outside group that helped spur attacks on Conger, raising questions about improper coordination, which the parties denied.

On Tuesday, Wehby and Moran decried the motivations behind those stories. “Dr. Wehby’s victory tonight sends a message that the ugly politics of personal destruction will not be tolerated in Oregon,” Moran said.

Now she’ll face Merkley and national Democrats, who had already dismissed the Republican field as not viable in Oregon. Still, Merkley is directly engaging, and he’s amassed a $3.7 million war chest for the fall. He had a 16- to 20-point lead on the Republicans in his own internal polling in April, though GOP pollsters suggest the race is closer.

About 25 percent of eligible voters had returned their primary ballots by Monday, according to the Oregon secretary of state’s office.

There was no immediate word from Conger about whether he’d support Wehby in the general election. He had expressed frustration with what he perceived as the NRSC’s preference for her.

He said on MSNBC late Tuesday that he’d made a “huge mistake” by simply trying to run a clean, issues-based campaign.

Key dynamics to watch in the fall include President Barack Obama’s job approval rating among Oregon voters, as well as attitudes about the president’s signature health care law. Democratic Gov. John Kitzhaber will be on the ballot, and voters may display their frustration with his role in the health law implementation, which could help Wehby.

But Democrats still have a significant registration and party infrastructure advantage.

“The best hope for any Republican here is going to be that, for whatever reason, the national Democratic party and national administration become substantially unpopular with Oregon voters,” said Portland-based pollster Tim Hibbits this week before the election.